The area of the isosceles triangle is cm 2 if the perimeter is 11 cm and the base is 5 cm.

Question

Philoid · Accepted Answer

Given Perimeter = 11cm

And a = 5

As the triangle is isosceles, b = c

Perimeter = 11

⇒ a + b + c = 11

⇒ 5 + b + b = 11

⇒ 5 + 2b = 11

⇒ 2b = 6

⇒ b = 3

So, we have a = 5, b = 3, c = 3

s = (a + b + c)/2

⇒ s = (5 + 3 + 3)/2 = 11/2

Area(Δ) = √s(s-a)(s-b)(s-c)

⇒ Area(Δ) =

⇒ Area(Δ) = (5√11)/4cm²

Hence, the statement is True.